Guys,
Personally I believe that the WSMs have run their course. When Winchester released the 300WSM, matching the 300WinMag (almost) in a short actioned rifle, that was novel and exciting. The 270WSM beat the 270Winchester and tread close to the 270Weatherby in a short action... that was a very useful gain. The 7mmWSM matches closely the 7mmRemMag and has not been greeted with as much enthusiasm. When Winchester blundered and released the 25WSSM rather than the 25WSM then I feel the momentum was lost. A 25WSM that matched the 257 Weatherby in a cheaper rifle would have been a sensation, but with the release of the 257Weatherby in the Vanguard, Winchester will never be able to chamber and release a 25WSM without stiff commercial opposition. For all intents and purposes the WSMs have done their job and slain the Rem SAUMs. If Winchester wanted to make a point, they'd release a 35WSM and put the final nail in the coffin of Remington's 350RM and the Whelen. But... a big bore would never be as popular as a small bore so I doubt it will ever happen. To release a 338WSM is superfluous, it will match a cartridge that has done a sterling job for over 30 years, shooters want something more, not just a rehash of an existing cartridge. Now a 338WSM or 35WSM in a modern Winchester lever or semi-auto action might be novel enough to sell some rifles.
Cheers...
Con